Raspberry Pi's firmware offers an interface though which update it's
clock's frequencies. This is specially useful in order to change the CPU
clock (pllb_arm) which is 'owned' by the firmware and we're unable to
scale using the register interface provided by clk-bcm2835.

Signed-off-by: Nicolas Saenz Julienne <redacted>
Acked-by: Eric Anholt <redacted>

---

Changes since v1:
  - Use BIT()
  - Add Kconfig entry, with compile test
  - remove prepare/unprepare
  - Fix uninitialized init.name in pllb registration
  - Add MODULE_ALIAS()
  - Use determine_rate() instead of round_rate()
  - Add small introduction explaining need for driver

 drivers/clk/bcm/Kconfig           |   7 +
 drivers/clk/bcm/Makefile          |   1 +
 drivers/clk/bcm/clk-raspberrypi.c | 302 ++++++++++++++++++++++++++++++
 3 files changed, 310 insertions(+)
 create mode 100644 drivers/clk/bcm/clk-raspberrypi.c

diff --git a/drivers/clk/bcm/Kconfig b/drivers/clk/bcm/Kconfig
index 29ee7b776cd4..a4a2775d65e1 100644
--- a/drivers/clk/bcm/Kconfig
+++ b/drivers/clk/bcm/Kconfig

@@ -64,3 +64,10 @@ config CLK_BCM_SR
 	default ARCH_BCM_IPROC
 	help
 	  Enable common clock framework support for the Broadcom Stingray SoC
+
+config CLK_RASPBERRYPI
+	tristate "Raspberry Pi firmware based clock support"
+	depends on RASPBERRYPI_FIRMWARE || (COMPILE_TEST && !RASPBERRYPI_FIRMWARE)
+	help
+	  Enable common clock framework support for Raspberry Pi's firmware
+	  dependent clocks

diff --git a/drivers/clk/bcm/Makefile b/drivers/clk/bcm/Makefile
index 002661d39128..eb7159099d82 100644
--- a/drivers/clk/bcm/Makefile
+++ b/drivers/clk/bcm/Makefile

@@ -7,6 +7,7 @@ obj-$(CONFIG_CLK_BCM_KONA)	+= clk-bcm21664.o
 obj-$(CONFIG_COMMON_CLK_IPROC)	+= clk-iproc-armpll.o clk-iproc-pll.o clk-iproc-asiu.o
 obj-$(CONFIG_ARCH_BCM2835)	+= clk-bcm2835.o
 obj-$(CONFIG_ARCH_BCM2835)	+= clk-bcm2835-aux.o
+obj-$(CONFIG_CLK_RASPBERRYPI)	+= clk-raspberrypi.o
 obj-$(CONFIG_ARCH_BCM_53573)	+= clk-bcm53573-ilp.o
 obj-$(CONFIG_CLK_BCM_CYGNUS)	+= clk-cygnus.o
 obj-$(CONFIG_CLK_BCM_HR2)	+= clk-hr2.o